L-赖氨酸产生菌FH128菌株的研究

Studies on L-Lysine Producing Strain FH128

以赖氨酸产生菌Ａ１１１（ＨＳ－、ＡＥＣ）为出发株，经化学诱变剂ＭＮＮＧ（Ｎ－甲基－Ｎ－硝基－Ｎ－亚硝基胍）及单氟醋酸处理获得单氟醋酸抗性突变株Ｆ７９，摇瓶发酵产Ｌ－赖氨酸盐酸盐７．０％－７．５％，对糖转化率３８％－４０％，分别比Ａ１１１株提高约２５％及２０％。然后，再以Ｆ７９菌为亲株经ＭＮＮＧ及噻唑丙氨酸处理获得噻唑丙氨酸抗性突变株ＦＨ１２８。在适宜的培养条件下，摇瓶发酵产Ｌ－赖氨酸盐酸盐８．５％－９．５％，最高产酸率１１％，对糖转化率４５％－５０％。在１６Ｌ自控发酵罐发酵，产Ｌ－赖氨酸盐酸盐１２％－１４％，对糖转化率４０％－４５％。在２０－１００ｍ３发酵罐发酵，产酸率为８．５％－９．５％，对糖转化率４０％－４２％，提取总收率８０％－８５％。成品（饲料级Ｌ－赖氨酸盐酸盐）质量符合国家标准（ＧＢ８２４５－８７）。ＦＨ１２８菌株遗传性能稳定，营养要求粗放，工艺较简单，便于工业化，三年前已应用于工业生产。

A resistant mutant of F79, the lysine Producer, was derived from the parent strain A111(HS-、 AEC') by mutation with MNNG (N - methyl - N' - nitro - N - nitrosoguanidine) and MF(Monofluoroacetic acid) .The Production of L - lysine· HCI of the mutant in flask was 7. 0% - 7. 5%, the conversion rate of glucose to L - lysine was 38% - 40%. The TA (α - Thiazol - DL - Alanine) resistant strain ＦＨl28 was derived from the Parent strain F79 by mutation with MNNG and TA. Under optimal culture conditions, the production of L - lysine· HCI was 8. 5% - 9. 5%; the maximum production of L lysine· HCI was 1l%, the conversion rate of glucose was 45% -50% in shake - flask, in 16 L fermenter, the production of L - lysine· HCI was 12% - 14%, the coversion rate was 40% - 45%. In 20 - 100m3 fermenter, the production of L - lysine· HCI was 8. 5% - 9. 5%,the conversion rate was 40% - 42%.